Such a fuel injection system is described in German Published Patent Application No. 197 25 076. For a sealing connection between a fuel injector and a respective coupling connection of a fuel distributor line, this injection system includes an annular gasket support which cooperates with a first sealing element for sealing off the gasket support from an end face of an inflow section of the fuel injector and includes a second sealing element for sealing off the gasket support from the coupling connection of the fuel distributor line. A bushing insertable into a fuel inlet opening of the inflow section passes through the annular gasket support, so that the gasket support is movably arrested in the radial direction between an upstream collar of the bushing and the inflow section of the fuel injector.
One disadvantage of the arrangement described in the publication cited above is that the bushing is an additional part which is manufactured with a low tolerance. The radial mobility of the gasket support is guaranteed only if it still has a certain axial play and is not pressed by the bushing against the inflow section, so the bushing is inserted to a precisely defined depth into the fuel inlet opening in assembly. This requires a precision finished cylindrical surface of the bushing and a bore produced with a corresponding fit as the fuel inlet opening in order to achieve a tight seating of the bushing, so that the required play for the gasket support is adjustable.
It is described in Unexamined Japanese Published Patent No. 08-312503 that a fuel injector insertable into a receiving bore and including an inflow section may be sealed by an O-ring on this inflow section with respect to a coupling connection of a fuel distributor line. The O-ring is in sealing contact with an inside wall of the coupling connection.
Due to the manufacturing tolerance of the receiving bore for the fuel injector as well as that of the coupling connection to the fuel distributor line, differences in position and angle occur between the inflow section of the fuel injector and the coupling connection of the fuel distributor. The O-ring situated between the inflow section of the fuel injector and the coupling connection of the fuel distributor line equalizes the differences in position and angle only to a very slight extent, which is inadequate. With regard to the differences in position and angle occurring in practice, in the case of the fuel injector system described in Unexamined Japanese Published Patent No. 08-312503, there is a risk of fuel escaping past the seal, which does not adequately compensate for the position and angle differences.